This Day in Sports History: April 23, 1989
With the first pick in the 1989 NFL draft, the Dallas Cowboys selected Troy Aikman, Quarterback, UCLA on April 23, 1989.

Naturally, with the first pick comes high expectations, and for Aikman, his start with the Cowboys was less than convincing of his number one overall status.
In his rookie season, the Cowboys were 0-11 in games that he started. He threw only nine touchdown passes and doubled that in interceptions.
But by his third season in the league, Aikman had grown into his stirrups, increasing his passer rating to 86.7 from 55.7 and 66.6 in his first two seasons, respectively.

In his fourth season came victory. Aikman lead Dallas to a Superbowl XVII win over the Buffalo Bills in 1992, and then again the following year, defeating the Bills for the second straight year to win the franchise’s fourth Super Bowl Championship.
Aikman spent all 12 years of his NFL career with Dallas, winning one more Super Bowl in 1995, which [at the time] put him at number three on the list of quarterbacks with the most Super Bowl wins, solidifying his place among the NFL’s greatest.

That 1989 first overall pick would live up to the expectations. A 3x Super Bowl Champion, Super Bowl XXVII MVP, and a 6x Pro Bowl selection, Aikman was elected into the Pro Football Hall of Fame in 2006.
But Aikman was not the only one from his draft class to make his way to Canton.
There were three other players picked in the top five that went on to NFL Hall of Fame careers.

Picked at number three, Barry Sanders was drafted by the Detroit Lions. Sanders spent 10 seasons in the NFL, all of them spent with Detroit. Sanders was a 10x Pro-Bowl selection and is 4th on the leagues All-Time leading rushers. He was elected to the Pro Football Hall of Fame in 2004.

With the fourth overall pick, the Kansas City Chiefs selected Derrick Thomas who was a Hall of Fame election in 2009. He is a 9x Pro Bowl selection and was fourth on the NFL’s All-Time Sacks leaders at time of his retirement.

Deion Sanders was selected at number five by the Atlanta Falcons. Sanders spent his first five seasons with Atlanta before stints with the San Francisco 49ers, Dallas Cowboys, Washington Redskins, and Baltimore Ravens. He is a 8x Pro Bowl selection, and a 2x Super Bowl Champion (San Francisco & Dallas). Sanders was elected into the Pro Football Hall of Fame in 2011.
References: profootballhof.com